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Ammonium hexabromomercurate(II)

chemical compound

Specimen drawers, botanical folios and brass scientific instruments under study light
Science and natureInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionMay 26, 2025
Entity authorityQ20979773 ↗
Source-derived summary

Ammonium hexabromomercurate(II) is a chemical compound with the chemical formula (NH4)4[HgBr6].

Synthesis

Heating of a mixture of mercury(II) bromide and ammonium bromide:

HgBr2 + 4NH4Br → (NH4)4[HgBr6]

Physical properties

The compound forms black crystals of tetragonal system, space group P4/mnc, cell parameters: a = 0.925560 nm, c = 0.88657 nm, Z = 2.

At a temperature of 200 K, the compound enters a phase of the monoclinic system, space group P21/n. At 250 K, it forms crystals of the orthorhombic system, space group Pnnm.

Editorial summary

“Ammonium hexabromomercurate(II)” enters the record as chemical compound. Crown Archives preserves that source wording while asking what Ammonium, hexabromomercurate and chemical can confirm, complicate or overturn.

Editorial reviewA sound reference starting point where classification, measurement and the date of the underlying evidence remain visible. The current 84-word lead offers orientation but no explicit four-digit date, so chronology should not be assumed. The selected authority fields contribute no independent date. Its strongest next move is a source search built around Ammonium, hexabromomercurate and chemical.
Editorial analysis

Why this record matters

“Ammonium hexabromomercurate(II)” is worth following because a concise public description often conceals a longer documentary argument. Here, Ammonium, hexabromomercurate and chemical provides the most credible route into that argument.

Evidence profile

The date and method of observation matter as much as the stated conclusion, especially where classification or consensus has changed. The source revision retrieved here is dated May 26, 2025. The linked authority identifier is Q20979773. None of the 0 selected statements returned an explicit reference.

Critical limits

Scientific names, classifications and consensus can change while older terminology persists in catalogues and historical literature. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

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Source & attribution

This entry incorporates text from “Ammonium hexabromomercurate(II)” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.